KRAS/NRAS/BRAF Mutation Rate in Saudi Academic Hospital Patients With Colorectal Cancer

RAS/RAF/MAPK Pathway Mutations as Predictive Biomarkers in Middle Eastern Colorectal Cancer: A Systematic Review

Background

This review article aims to investigate the prevalence and spectrum of rat sarcoma (RAS) and V-Raf Murine Sarcoma Viral Oncogene Homolog B (BRAF) mutations, and their connection with geographical location, clinicopathological features, and other relevant factors in colorectal cancer (CRC) patients in the Middle East.

Methods

A systematic literature review, employing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework, was conducted to investigate the association between the frequency of relevant mutations and the descriptive clinicopathological characteristics of CRC patients. Multiple electronic databases, including PubMed, Science Direct, Web of Science, Scopus, and Google Scholar, were searched to analyze the relevant literature.

Results

A total of 19 eligible studies comprising 2960 patients with CRC were included in this review. A comprehensive analysis of the collected literature data as well as descriptive and methodological insights is provided. Men were predominant in reviewed studies for the region, accounting for 58.6%. Overall, RAS mutation prevalence was 38.1%. Kirsten RAS Viral Oncogene Homolog (KRAS) mutations were the most common, accounting for 37.1% of cases and distributed among different exons, with the G12D mutation being the most frequent in exon 2 (23.2%) followed by G12V (13.7%), G13D (10.1%), G12C (5.1%), G12A (5.04%), and G12S (3.6%). Neuroblastoma RAS Viral Oncogene Homolog (NRAS) mutations were identified in 3.3% of tumor samples, with the most common mutation site located in exons 2, 3, and 4, and codon 61 being the most common location for the region. The total mutation frequency in the BRAF gene was 2.6%, with the V600E mutation being the most common.

Conclusion

The distribution patterns of RAS and BRAF mutations among CRC patients exhibit notable variations across diverse ethnic groups. Our study sheds light on this phenomenon by demonstrating a higher prevalence of KRAS mutations in CRC patients from the Middle East, as compared with those from other regions. The identification of these mutations and geographical differences is important for personalized treatment planning and could potentially aid in the development of novel targeted therapies. The distinct distribution patterns of RAS and BRAF mutations among CRC patients across different ethnic groups, as well as the regional variability in mutation prevalence, highlight the need for further research in this area.

Molecular pathology of colorectal cancer: The Saudi situation in perspective

Colorectal cancer (CRC) is one of the most common cancers worldwide, and one of the most common causes of cancer deaths. In recent times, significant advancements have been made in elucidating the molecular alterations of the disease, and the results have been an improved understanding of CRC biology, as well as the discovery of biomarkers of diagnostic, prognostic, and therapeutic significance. In this review, an evaluation is carried out of the molecular pathology research of CRC emanating from Saudi Arabia. The verdict is that the data on the molecular alterations in CRC from Saudi patients is at best modest. This dearth of molecular pathology data is aptly reflected in the paucity of molecular markers recommended for testing by the Saudi National Cancer Centre guidelines for CRC management. Large scale multi-institutional and multiregional translational studies are required to generate molecular data that would inform diagnostic, prognostic, and risk-stratification guidelines for Saudi CRC patients.

Metastatik Kolorektal Kanserli Hastalarda KRAS/NRAS Gen Mutasyon Profilleri

Amaç: RAS genleri, Epidermal Büyüme Faktörü Reseptörü (EGFR) tarafından indüklenen RAS-MAPK Sinyal yolağının bir üyesidir. Bu yolaktaki genlerde meydana gelen mutasyonlar kanser gelişimini tetiklemektedir. Kolorektal kanserde (KRK), RAS genlerinde meydana gelen mutasyonlar EGFR hedefli tedaviye karşı direnç gelişimine neden olur. EGFR monoklonal antikorları, kemoterapötik ajanlar olarak metastatik kolorektal kanser tedavisinde yaygın şekilde kullanılmaktadır. KRAS mutasyonları KRK’nın 30-50%’sinde, NRAS mutasyonları ise 2-3%’ünde bulunur. Bu çalışmada, KRK’lı hastalarda KRAS/NRAS mutasyonlarını analiz etmeyi amaçladık. Yöntem: EGFR-hedefli tedaviye direnç gösteren 100 metastatik KRK hastası, Real-Time Polimeraz Zincir Reaksiyonu yöntemi ile KRAS mutasyonu (ekzon 2, 3, 4) ve NRAS mutasyonu (ekzon 2, 3, 4) durumu için tarandı. Bulgular: Bu çalışma sonucunda, KRAS mutasyonu oranı 48% ve NRAS mutasyonu oranı 1,92% olarak bulundu. En yaygın KRAS mutasyonları kodon 12’de saptandı. Kodon 12 mutasyonlarının dağılımı G12V (25%), G12D (23%), G12C (14,5%) olarak elde edildi. Sonuç: Çalışmamızda saptanan KRAS ve NRAS mutasyon sıklıkları benzer raporlar ile uyumlu bulundu. Sonuçlarımız, RAS mutasyonlarının test edilmesinin EGFR-hedefli tedaviden fayda sağlayacak hastaları belirlemede hayati rolünü desteklemektedir.